Self-contained, moving needle syringe with hydraulic safety lock

ABSTRACT

A SYRINGE FOR INJECTING AN INJECTABLE PREPARATION INTO A MUSCLE OR AREA OF A BODY OTHER THAN A VEIN OR ARTERY. THE SYRINGE INCLUDES A HOUSING HAVING A SUPPLY CHAMBER WHICH IS ADAPTED TO CONTAIN THE INJECTABLE PREPARATION IN A TANDEM ARRANGEMENT WITH A VACUUM CHAMBER WHICH IS FLUID-TIGHTLY SEPARATED FROM THE SUPPLY CHAMBER. AN ELONGATED HOLLOW NEEDLE EXTENDS INTO THE HOUSING AND HAS AN OUTLET END WHICH IS ADAPTED TO PENETRATE INTO THE BODY AND THROUGH WHICH THE INJECTABLE PREPARATION DISCHARGES, THE NEEDLE HAVING AN INLET FOR RECEIVING THE INJECTABLE PREPARATION. INITIALLY, HOWEVER, THIS INLET IS DISPLACED THROUGH THE VACUUM CHAMBER FOR REACHING THE SUPPLY CHAMBER. THE MOVEMENT OF THE INLET OF THE NEEDLE THROUGH THE VACCUUM CHAMBER IS BROUGHT ABOUT WHILE THE OUTLET END OF THE NEEDLE PENETRATES INTO THE BODY,   SO THAT IF THE OUTLET END OF THE NEEDLE SHOULD HAPPEN TO PENETRATE INTO A VEIN OR ARTERY BLOOD WILL FLOW IN A REVERSE DIRECTION THROUGH THE NEEDLE INTO THE VACUUM CHAMBER. THE HOUSING CONTAINS A HYDRAULIC-TYPE BLOCKING DEVICE WHICH RESPONDS TO THE FLOW OF BLOOD INTO THE VACUUM CHAMBER FOR BLOCKING MOVEMENT OF THE INLET OF THE NEEDLE INTO THE SUPPLY CHAMBER, SO THAT IN THIS WAY INJECTION OF THE PREPARATION INTO A VEIN OR ARTERY IS AUTOMATICALLY PREVENTED.

United States Patent Eric S. Lichtenstein 24 E. 93rd St., New York, N.Y. 10028 [21] Appl. No. 857,985

[22] Filed Sept. 15, 1969 [45] Patented June 28, 1971 [72] Inventor [54] SELF-CONTAINED, MOVING NEEDLE SYRINGE WITH HYDRAULIC SAFETY LOCK 9 Claims,3 Drawing Figs.

[52] US. Cl 128/215,

128/220, 128/221 [51] Int. Cl A6Im 5/18 [50] Field ofSearch 121/221,

Primary Examiner.1ose'ph S. Reich At!orney--Blum, Moscovitz, Friedman and Kaplan ABSTRACT: A syringe for injecting an injectable preparation into a muscle or area ofa body other than a vein or artery. The syringe includes a housing having a supply chamber which is adapted to contain the injectable preparation in a tandem arrangement with a vacuum chamber which is fluid-tightly separated from the supply chamber. An elongated hollow needle extends into the housing and has an outlet end which is adapted to penetrate into the body and through which the injectable preparation discharges, the needle having an inlet for receiving the injeetable preparation. Initially, however, this inlet is displaced through the vacuum chamber for reaching the supply chamber. The movement of the inlet of the needle through the vacuum chamber is brought about while the outlet end of the needle penetrates into the body, so that if the outlet end of the needle should happen to penetrate into a vein or artery blood will flow in a reverse direction through the needle into the vacuum chamber. The housing contains a hydraulictype blocking device which responds to the flow of blood into the vacuum chamber for blocking movement of the inlet of the needle into the supply chamber, so that in this way injection of the preparation into a vein or artery is automatically prevented.

SELF-CONTAINED, MOVING NEEDLE SYRINGE WITII HYDRAULIC SAFETY LOCK BACKGROUND OF THE INVENTION The present invention relates to syringes.

In particular, the present invention relates to syringes for injecting preparations into the body, these injectable preparations being in the form of fluid medication drugs, or the like, capable of being injected by a physician or nurse into the body of a patient, for example.

One of the problems encountered with syringes of this general type is that the injectable preparation or liquid preparation must not be injected into an artery or vein. For example, the injectable preparation should be injected into a muscle. However, at the present time if by chance the needle penetrates into a vein or artery, the injectable preparation will improperly be introduced into the vein or artery, and the physician or nurse may be completely unaware of this fact at the time of the injection.

A second problem is two-fold. When injected medication distends a single tissue plane and is confined to a space at this tissue plane, the extent of absorption is decreased and it is possible for a sterile abscess to form. Thus, these further problems are encountered with conventional syringes of the above general type.

SUMMARY OF THE INVENTION It is accordingly a primary object of the present invention to provide a syringe which will avoid these drawbacks.

In particular, it is an object of the invention to provide a disposable, self-contained syringe which will operate in a manner preventing introduction of the injectable preparation into a vein or artery, spreading medication through multiple tissue planes.

Thus, it is an object of the invention to provide a syringe which blocks itself against discharging the injectable preparation in the event that the outlet end of the needle penetrates into a vein or artery.

Yet another object of the invention is to provide a disposable, self-contained syringe of this type which is inexpensive and fully reliable in operation while at the same time capable of achieving additional advantages such as automatic application of an antiseptic preparation at the area of the skin through which the needle penetrates.

The objects of the invention also include incorporating into a syringe a moving needle capable of penetrating multiple tissue planes to spread medication for enhanced absorption while preventing sterile abscess formation.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a longitudinal sectional elevation of one possible embodiment of a syringe according to the invention, with a closure cap protecting the discharge end prior to use;

FIG. 2 is a section similar to FIG. 1, after the cap has been removed and after the outlet end of the needle has penetrated a vein or artery; and

FIG. 3 is a section similar to FIG. 2 after the outlet end of the needle has not penetrated a vein or artery.

DESCRIPTION OF A PREFERRED EMBODIMENT As is apparent from the above considerations, the syringe of the present invention is that type of syringe which is designed to introduce an injectable preparation into some part of the body other than the veins or arteries thereof. As may be seen from FIG. 1, the syringe 10 includes an elongated housing 12 which may be of cylindrical configuration and which preferably has a circular cross section. The housing 12 has a front open end 14 and a rear closed end 16. This housing 12 of the syringe 10 may be made from any suitable plastic, and while it is possible to use glass, for example, plastics wellknown for this purpose are preferred.-

The syringe includes an elongated hollow needle 18 which has an open outlet end 20 adaptedto penetrate into the body, as shown in FIGS. 2 and 3. Distant from the outlet 20 the elongated hollow needle 18 has an inlet 22. The needle 18 has distant from the outlet 20 a U-shaped portion 24 which is provided with the relatively short leg 26 terminating in the inlet 22 which forms the inlet end of the needle.

When the parts are assembled the needle 18 is displaced through a transverse wall 28 with the outlet end 20 of the needle first penetrating through and passing beyond the wall 28, and the displacement of the needle through the wall 28 is continued until the inlet 22 penetrates into but does not pass through the wall 28, so that in this way the inlet 22 is closed by the wall 28. This wall 28 is made, for example, of a plastic which may be of the same material as that which is used for the housing 12 and which has the property of enabling the inlet end 22 of the needle to penetrate to the left, as viewed in FIG. I, through and beyond the wall 28 without any tendency for the material of the wall 28 to become fragmented so as to in any way plug the inlet 22.

With the needle 18 thus assembled with the transverse wall 28, the latter is slidably introduced into the housing 12, and some of the air in the space between wall 28.and the end 16 being evacuated by conventional means, so that a low pressure space is formed between the wall 28 and the closed end 16 of the housing 12. The outer periphery of the wall 28 has a slidable but fluidtight engagement with the inner surface of the housing 12. The inner surface of the closed end 16 of the housing 12 is formed with a substantially semicircular indentation for receiving the right end of the needle 18, as viewed in FIG. 1.

Then a coil spring 30 is placed around the needle 18 on the left side of the wall 28, as viewed in FIG. 1.

At this time a partition 32 is displaced along the needle 18 the housing I2 to the location shown in FIG. 1 where the spring 30 is compressed to some extent. This partition 32 also may be made of the same plastic material as the wall 28 and housing 12 and has a relatively tight friction fit in the housing to have a fluidtight engagement therewith, Of course, it is also possible to mount both the transverse wall 28 and the partition 32 on the needle with the spring 30 between elements 28 and 32 so that then this assembly can be introduced as a unit into the housing 12. Some of the air in the space between the partitions 28 and 32 is evacuated by conventional means providing a vacuum chamber 34 in which a relatively low pressure, substantially less than atmospheric pressure, prevails.

This partition 32 defines with the interior of the housing 12 at the side of the partition opposite from the wall 28 a supply chamber 36 which receives the injectable preparation 38 which can be any suitable medicinal liquid, for example, which is to be introduced into the body of the patient. This preparation 38 is introduced into the supply chamber 36 under proper hygienic conditions, which is true of all of the assembly operations, and of course known measures are taken to prevent contamination of any of the parts of the syringe.

With the parts still in an evacuated atmosphere a plunger 40 is introduced into the housing 12 through the open end 14 thereof. This plunger 40 has a closed end 42 which extends up to the preparation 38 to define the end of the supply chamber 36 opposite from the partition 32. The plunger has an elongated tubular portion 44 which extends forwardly beyond the open end 14 of the housing 12 and which terminates in an open end 46 which receives a pad 48 of gauze or other absorbent material in which an antiseptic liquid is located. If I desired, the wall of the plunger 40 may be made much thicker than illustrated in FIG. 2 so that the wall extends radially inwardly much more closely to the needle to provide a fairly narrow channel in the plunger through which the needle extends. In this way lateral support will be given to a relatively thin needle so as to prevent flexing or bending thereof during injection. Initially the hollow needle 18 extends through the interior of the tubular portion 44 of the plunger to have its outlet end 20 situated in antiseptic pad 48. Thus, the plunger need only have its end 42 displaced along the needle until the parts have the position shown in FIG. 1, and then the pad 48 can be introduced to cover the outlet 20 of the needle.

Thereafter an elongated tubular closure 50 is placed in a closing position surrounding the part of the plunger which extends forwardly beyond the open end 14 of the housing 12. This closure 50 has a'front closed end and a rear open end butting against the open end 14 of the housing 12. Any suitable adhesive may be used to maintain the cap 50 releasably in the position shown in FIG. 1, or, if desired, an adhesive tape may extend around the exterior of the closure 50 and housing 12 bridging the interface between the engaging end edges of the closure 50 and housing 12.

When the syringe is to be used the cap 50 is removed so that the plunger 44 is exposed. Then the pad 48 is placed against the skin of the individual at the area through which the needle is to penetrate. The operator will now engage the end 16 of the housing 12 and displace it toward the individual so that the plunger 40 and the end 16 of the housing 12 aPproach each other. The frictional resistance to movement of the transverse wall 28 in the housing 12 and force of the spring 30 are such that initially the vacuum space will be maintained as the inlet 22 penetrates through the wall 28 to be received in the vacuum chamber 34. Now the displacement of the end 16 of the housing 12 toward the plunger 40 continues to that the inlet 22 moves through the vacuum chamber 34 to the partition 32. At the same time the outlet end of the needle 18 penetrates further into the body of the individual.

If it should happen that during this phase of the operation the end 20 of the needle penetrates into a vein or artery, then blood from the vein or artery will immediately ,flow into the needle through the outlet 20 thereof and then out through the inlet 22 into the vacuum chamber 34 to fill the vacuum chamber 34. FIG. 2 shows this situation where blood 52 has entered into the vacuum chamber 34. Continued injection pressure at this point will expel blood until needle end 22 enters partition wall 32. In this way there will be an effective ceiling of a volume of blood within the chamber 34. This sealed volume of blood will form an incompressible hydraulic block acting to prevent very effectively penetration of inlet 22 into the supply chamber 36. This hydraulic blocking structure is very effective and the physician, nurse, or the like will immediately see blood or feel the difficulty in continuing the advance of the housing l2 and will know that it is necessary to remove the syringe and to repeat the operation with another syringe. it is to be noted, however, that even if there is no recognition of the fact that the hydraulic blocking structure is operating, the injection nevertheless will be automatically and effectively prevented.

On the other hand, if the end 20 of the needle penetrates into a part of the body where there is no vein or artery as illustrated in FIG. 3, then the partition 32 will not have its movement toward the wall 28 blocked by any fluid introduced into the vacuum chamber 34, so that the parts can continue to operate until they reach the position shown in FIG. 3 where the inlet 22 of the needle has penetrated through the partition 32, in opposition to the force of the spring 30 which becomes compressed, into the supply chamber. Now during the continued displacement of the housing 12 to the left, as viewed in FIG. 3, the injectable preparation 38 will be displaced out of the supply chamber 36 into the needle and out through the outlet end 20 thereof into a proper part of the body. The motion of the advancing needle will dispense the preparation through multiple tissue planes.

it is therefore apparent that while the above-described structure is quite simple, inexpensive, and easy to operate in a fully hygienic manner, including such features as the automatic location of the antiseptic pad 48 against the skin through which the needle penetrates, this structure will operate in a fully reliable and fully automatic manner to provide a hydraulic block which will reliably prevent injecting of the preparation 38 into a vein or artery. Also, when operational, the structure will inject medication by effectively spreading preparations through multiple tissue planes.

It is to be particularly noted that with the above-described structure of the invention the outlet end of the needle moves through multiple tissue planes perpendicularly thereto during operation of the syringe. This will provide the advantage of spreading medication through multiple tissue planes so as to enhance absorption into the blood while preventing the formation of a sterile abscess. This latter undesirable result is likely to occur when the injected preparation is confined within a distended tissue space. Thus, the needle will move substantially perpendicularly to the major blood vessels. The hydraulic block will prevent initial intravascular injection while this particular anatomic relationship will prevent substantial intravascular administration of a preparation during injection.

lclaim:

1. In a syringe, a housing having in its interior a supply chamber adaptedv to contain an injectable preparation and a vacuum chamber fluid-tightly separated from said supply chamber, an elongated hollow needle having an outlet end through which the injectable preparation is adapted to be discharged and an open inlet distant from said outlet end and situated within said housing, said housing, having a pair of portions movable one relative to the other and coacting with said hollow needle for. displacing, during penetration of said outlet end of said needle into a body which is to receive an injection, said inlet of said needle first along the interior of said vacuum chamber and then into said supply chamber to receive the injectable preparation therefrom, so that if said outlet end of said needle penetrates into a vein or artery, blood will flow through said needle into said vacuum chamber of said housing through said inlet of said needle, and means carried by said housing for blocking movement of said needle inlet to said supply chamber when blood enters said vacuum chamber, so that the injectable preparation cannot be injected if the needle has penetrated into a vein or artery.

2. The combination of claim 1 and wherein said blocking means includes a partition extending transversely within the housing and through which said hollow needle extends, said partition fluid-tightly separating said supply and vacuum chambers from each other so that said partition defines part of each of said chambers, one of said pair of portions comprising a slidable plunger located within the housing on that side of said partition where said outlet end of said needle is located, said slidable plunger defining an end of said supply chamber opposed to said partition, and the other ofsaid pair of portions comprising a displacing portion located on the side of said partition opposite from said plunger and adapted to engage said needle to displace the latter through said partition with said inlet of said needle first moving through said vacuum chamber before reaching said supply chamber.

3. The combination of claim 2 and wherein said housing has distant from said plunger a closed end engaging said needle and forming said displacing portion of said housing.

4. The combination of claim 3 and wherein said blocking means includes a slidable wall extending transversely across the interior of said housing and fluid-tightly but slidably engaging the latter, said transverse wall being situated between said closed end of said housing and said partition and defining the vacuum chamber with said partition, the hollow needle extending through said slidable wall and terminating distant from said outlet end in a substantially U-shaped portion engaging said closed end of said housing and having a relatively short leg terminating in an open inlet end to form the inlet of said needle, said inlet end extending into said transverse wall to be closed thereby but then being adapted to be displaced through said transverse wall into said vacuum chamber while said plunger and closed end of said housing approach one another, said inlet end of said needle being made to penetrate through said partition during continued displacement of said plunger and closed end of said housingtoward one another, to receive the injectable preparation in said supply chamber.

5. The combination of claim 4 and wherein a spring surrounds said needle in said vacuum chamber for opposing movement of said'slidable wall toward said partition.

6. The combination ofclaim 3 and wherein said plunger is in the form of a tubular member terminating at one end in a wall slidably received in said housing and having an opposite open end where the outlet end of said needle is initially located, so that the open end of said plunger can be situated at the location through which the outlet end of the needle is to penetrate.

7. The combination of claim 6 and. wherein a pad containing an antiseptic material is located in said open end of said plunger and receives the outlet end of said needle so that the pad when applied to the location through which the outlet end of the needle is to penetrate will apply the antisepticautomatically at the location through which the outlet end of the needle penetrates.

8. The combination of claim 6 and wherein a closure cap forms a removable extension of said housing and covers a part of the plunger which extends forwardly beyond said housing, so that upon removal of said cap the plunger is exposed in preparation for operation of the syringe.

9. The combination of claim 2 and wherein said housing is in the form of an elongated cylinder and said plunger is in the form of an elongated tube extending slidably into said cylinder and extending forwardly beyond the latter. 

